Objective To evaluate the effect of exogenous epidermal growth factor (EGF) on promoting nerve regeneration after terminolateral neurorrhaphy (TLN). Methods Thirty-two adult Wistar rats were randomly divided into 2 groups. In the EGF group,the left peroneal nerve was transected,then an 1mm epineural window was created on the neighbouring tibial nerve. The distal end of peroneal nerve was sutured to the windowed tibial nerve by means of end-to-side attachment. in the control group,nerve TLN was performed as In the EGF group. Injection of EGF/normal saline (20?g/10?l) and normal saline (10?l) was done at the distal site of peroneal nerve transected in the EGF group and control group for two weeks respectively. Histological,morphological and electrophysiological examinations were performed in 4 and 8 weeks after the operation. Results The cross area of the regenerated myelinated nerve fibres,axon numbers,motor nerve conduction velocity were significantly better in the EGF group than in the control group ( P

Objective: To study the relationship between slow coronary lfow (SCF) and coronary microcirculatory dysfunction in relevant patients and to explore the risk factors for SCF development. Methods: Our research was conducted in 2 groups: SCF group, the patients with coronary angiography conifrmed diagnosis and Control group, the subjects with normal coronary lfow.n=32 in each group. The general information, blood levels of biochemical indicators, hs-CRP levels, TIMI lfow frame and the index of microcirculatory resistance (IMR) were examined, their relationships to SCF were analyzed. Results: Compared with Control group, the patients in SCF group showed the lower levels of HLL-C (1.57 ± 0.38) mmol/L vs (1.62 ± 0.43) mmol/L and Apo-A1 (1.41 ± 0.31) mmol/L vs (1.57 ± 0.38) mmol/L, while higher level of hs-CRP (3.63 ± 1.67) μg/mL vs (1.74 ± 0.75) μg/mL; SCF groups had increased IMR (29.28 ± 7.68) vs (24.94 ± 6.67), all P<0.05. IMR was positively related to TIMI lfow frame (r=0.766, P=0.019) and hs-CRP (r=0.565, P=0.000). Conclusion:①Microcirculatory dysfunction was related to SCF.②Inlfammatory reaction, decreased blood levels of HDL-C and Apo-A1 might be involved in pathological process of SCF.

0.05).[Conclusion]The values of three-dimensional parameters in old femoral neck fracture patient are different with that of normal persons in the loading region of the femoral head although there is no difference in BMD values between them.This may provide new evidence to predict osteoporotic femoral neck fracture.

Objective To observe the effect of based biomimetic biphasic calcium phosphate(BCP)tissue engineered bone masses to repair the bone defects and prevent the collapse of femoral head in dogs.Methods Biomimetic BCP ceramic scaffolds was fabricated using three-dimensional(3D)gel-lamination technology according the micro-computed tomography(Micro-CT)information of cancellous bone of dogs' femoral heads.Tissue engineered bone masses were constructed by the combination of biomimetic BCP scaffolds and induced osteogenic bone marrow stromal cells(BMSCs)in vitro.In 10 dogs,tissue engineered bone was implanted into the bone defect on the weight-bearing area of femoral head.In the control group of another 10 dogs,autogenous cancellous bone chips were impressed into the bone defect on the weight-bearing area of femoral head.The gross appearance and regeneration of new bone were observed in 30 weeks postoperatively.Results The fabricated biomimetic BCP scaffolds had better 3D structure.The trabecular system of the scaffolds had some orientation along the weight-bearing line of femoral head and represented plate-like model.BMSCs grow flourishing on the surface of the scaffolds.After 30 weeks operatively,in the tissue engineered bone implanted dogs,the gross appearances of the femoral head were integrity and a great lot of new bone tissue wraps the trabecula of the scaffolds under microscope.In the control group,the mostly femoral heads were collapse gross appearance.Conclusion Tissue engineered biomimetic BCP had better biocompatibility and could prevent the collapse of femoral head after it is implanted into the bone defects of femoral head.

[Objective]In order to dynamically observe the ossification process by living small animal Micro-CT in a rat femur distraction osteogenesis (DO) model,the author applied a special designed external fixiator system. [Methods]A femur DO model was made on 12 SD rats.After 7 days of latency,the femurs were distracted at a speed of 0.25 mm every 12 hours for 14 days.At the first day of consolidation period,the steel external fixiators were substituted by radio-transparent polymer splint material made fixiators.At 7 and 21 days of consolidation period,two randomly selected rats were sacrificed for histological examination.The other 8 rats were selected for X-ray and living Micro-CT examination at 0,7,21,35 days of consolidation period.All animals were sacrificed at 35 days of consolidation period,5 for biomechanical test,3 for histological examination.[Results]There was no significant new bone formed in distracted zone at latency and distraction periods.The volume of distracted zone increased little in the following 5 weeks of consolidation period.Bone volume,bone mineral content,bone volume fraction,and the number of trabeculae all increased over the consolidation period,while mineral content of mineralized tissue and thickness of traleculae did not increased until 3 weeks after consolidation began.At final observation (56 days post operation),there still exist un-mineralized cartilage tissues in the central of distracted zone,and the distracted femurs had lower biomechanical property when compared with corresponding normal femurs.[Conclusion]1) Radio-transparent polymer splint is a satisfactory substitute of steel external fixator.2) Micro-CT is a useful tool for dynamical observing and evaluating bone formation status in DO model.3) The increasing of bone volume began at the end of distraction,lasting at least 5 weeks,while the remodeling of new formed bone began 3 weeks after distraction ended.The increasing and remodeling of new formed bone was not concord.This result indicates that,in order to obtain proper results,the corresponding interference should be taken at different time points.

0.05). Peak force test maximal displacement evaluation and failure energy absorption measurement showed that hamstring tendon knot or bone bolt press fit implant fixation were significantly better than B-PT-B (P0.05). Conclusion Reconstruction of ACL by hamstring tendon knot or bone bolt press fit implant fixation and tibia side tendons by weaving suture to tie a knot on the bone bridge can meet daily physiological demand.

Objective To study the biomechanical strength of calcium phoshphate cement (CPC) in fixating distal radial fractures. Methods A total of 18 human distal radius fracture models were made and randomly divided into three groups: fixed with Kirschner wire (Kirschner group), CPC (CPC group) or CPC combined with Kirschner wire (combination group). Compression test was performed to measure compression rigidity and rotational angle of distal fragment at 100 N and anticompression strength and maximum compression strength at 2 mm displacement. Results Compression rigidity, distal fragment rotation angle in coronal or sagittal plate had no significant statistical difference at 100 N of compression in three groups. Compression strength at 2 mm displacement in CPC group (average 375 N) and combination group (average 386 N) exceeded that in Kirschner group (average 116 N), with significantly statistical difference (P

ObjectiveTo observe the effect of rabbit skeletal muscle stem cells (RSMSCs) modified by adenovirus mediated bone morphogenetic protein-2 (BMP-2) gene ex vivo in combination with demineralized bone matrix (DBM) on repair of longer bone defect in rabbit.MethodsModel of radial bone defects (20 mm) of rabbits was established. 50 rabbits were divided into 5 groups, group A (AdrhBMP-2 trusduced RSMSCs/DBM group), group B (adGFP trusduced RSMSCs/DBM group), group C (not trusduced RSMSCs/DBM group), group D (DBM group), and group E (untreated group). Roentgenographic, histologic, biomechanical, bone density of all animals were examined at the end of 4th and 6th week after surgery.ResultsAt 4th week, radial bone defects healed in group A. The healing rates from group A to group E were 100%, 50%, 33%, 0%, and 0% respectively at 6th week.ConclusionRSMSCs modified by AdrhBMP-2 ex vivo in combination with DBM can repair radial longer segemental defect in rabbit. It's possible to be used in the clinical treatment of longer segemental bone defect.

BACKGROUND: An effective preservation method must preserve the integrity of tissue structure. OBJECTIVE: To compare the effects of vitrification and cryopreservation method on the artery morphology and mechanical properties. DESIGN, TIME AND SETTING: The randomized controlled animal experiment was done at the Department of Orthopedics, General Hospital of Chinese PLA, between September 2001 and August 2004. MATERIALS: Eighteen New Zealand rabbits were randomly divided into vitrified artery group, cryopreserved artery group and fresh artery group, with 6 rabbits in each group. METHODS: Femoral arteries were removed from rabbits and put in balanced solution. Arteries in the vitrified artery group were immersed in the 25%, 50% and 100% gradient vitrified solution at 4 ℃ and then were put in liquid nitrogen. Arteries in the cryopreserved artery group were cooled from normal temperature to 0, -20, -70 ℃, and balanced for 60 minutes, then were put in liquid nitrogen. Samples were preserved in liquid nitrogen for more than 14 days. MAIN OUTCOME MEASURES: The morphology changes of preserved arteries observed through naked eye and microscope; hysteresis loop; stress relaxation; breaking strength. RESULTS: Artery structures were all preserved well in the three groups, the integrity rate of vitrified artery group was 91.67%, which was significantly better than 54.17% of cryopreserved artery group (P 0.05). CONCLUSION: There influences of vitrification and cryoprsesrvation on the artery morphology and mechanical properties were not significant, while arteries preserved by vitrification had less tissue ruptures, so vitrification is suitable for preserving long vessels.

BACKGROUND: It is proved that nerve regeneration induced by terminolateral neurorrhaphy(TLN) is not as active as that induced by end-to-end suture. Exogenous epidermal growth factor(EGF) increases the opportunity of neuron survival in vitro and promotes nerve regeneration. Whether it can increase nerve regeneration after terminolateral neurorrhaphy deserves further study.OBJECTIVE: To evaluate the effect of exogenous EGF in promoting nerve regeneration after terminolateral neurorrhaphy.DESIGN: A randomized controlled trial.SETTING: Orthopedic Institute of Chinese PLA General Hospital.PARTICIPANTS: The trial was conducted in the Orthopedic Institute of Chinese PLA General Hospital from September 2001 to February 2002. A total of 32 male Wistar rats, weighting 200- 250 g, were randomized to control group and EGF group with 16 rats in each group.METHODS: The right peroneal nerve was transected and an epineural window of 1 mm was created on the neighboring tibial nerve. The distal end of the transected peroneal nerve was sutured to the windowed tibial nerve by means of end-to-side attachment. Each rat in EGF group received injection of 0. 1 mL/d EGF diluted with normal saline at 2 g/L for two weeks while each in control group received injection of normal saline (0. 1 mL/d) at the distal site of the transected peroneal nerve for two weeks. Histological, morphological and electrophysiological examinations were performed 4 and 8 weeks after operation.MAIN OUTCOME MEASURES: The regeneration rate of myelinated nerve, motor nerve conduction velocity and ultrastructural changes of the two groups.rate of myelinated nerve fibers: 4 and 8 weeks after operation, it was better in EGF group[ (52.42 ± 1.45)% and(61.41 ± 1.54)% ] than that in control nerve conduction velocity: 4 and 8 weeks after operation it was obviously greater in EGF group[ (30. 33 ±0. 88)m/s and(34. 36 ± 1.09)m/s] than that in conObservation of ultrastructure: The number of myelinated nerve fibers, and the thickness and maturation degree of myelin sheath were significantly better than those in control group.CONCLUSION: Exogenous EGF can promote nerve regeneration, increase nerve conduction velocity after terminolateral neurorrhaphy.